Mathematics · 2024
JEE Main · 29 January 2024, Shift 2 · Q18
If the mean and variance of five observations are 24/5 and 194/25 respectively and the mean of the first four observations is 7/2, then the variance…
If the mean and variance of five observations are $\displaystyle \frac{24}{5}$ and $\displaystyle \frac{194}{25}$ respectively and the mean of the first four observations is $\displaystyle \frac{7}{2}$, then the variance of the first four observations in equal to
Official answer
From NTA’s final answer key for this paper.
(3)
$\displaystyle \frac{5}{4}$
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JEE Main 2024 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.